The subject application disclosed yarn control and feeding apparatus in which concepts from tufting procedures which have become known as the "Spanel tufting system" are utilized. Generally, the Spanel system utilizes pneumatic means to transport yarn to a tufting station, either in metered lengths of unsevered yarn or in discrete bits, after which time the yarn is tufted, by needles or other bit-applying elements to a backing layer to form a tufted product such as a rug.
The present invention discloses yarn control and feeding apparatus which, in some respects, operationally improves embodiments of early Spanel patents, including U.S. Pat. No. 3,554,147, which issued to Abram N. Spanel and George J. Brennan on Jan. 12, 1971, and U.S. Pat. No. Re. 27,165, which issued Aug. 10, 1971 to Abram N. Spanel and Lloyd E. Barton.
The aforementioned U.S. Pat. No. Re. 27,165 discloses a pneumatic yarn transport system having multicolor selection capability in which yarn strands and/or discrete bits of yarn are transported pneumatically to a tufting station where they are applied by tufting elements to a backing layer. The aforementioned U.S. Pat. No. 3,554,147 describes an alternative system to U.S. Pat. No. Re. 27,165, and provides for the simultaneous selection of bit-lengths of yarn of various colors for each tufting cycle at each individual tufting station. A collator structure in which individual channels transport yarn into a common passageway adjacent the tufting station is utilized. The capability of severing a bit-length of yarn before, during or after threading of the tufting element and before or during actual tufting is disclosed.
In addition to the above Spanel patents, co-pending Spanel Application Ser. No. 419,417 discloses a tufting device which utilizes a cutting arrangement employing an axially reciprocable passageway section to provide access for yarn severing means to sever the yarn into selectively sized yarn bits. In addition, co-pending Spanel Application Ser. No. 474,264 discloses a tufting machine which includes a rotatable yarn feed having modified driving and brake means engageable with said rotatable yarn feed means. A pneumatic yarn transport means is provided which includes selective control of gas flow for transporting metered lengths of yarn to a tufting station for severance into yarn bits and subsequent implantation into a backing. As in U.S. Pat. No. 3,554,147, a collator structure is utilized which leads into a common passageway adjacent the tufting station. A yarn pullback or retraction means for retracting yarn from the common passageway is disclosed which will cause only minimal yarn deformation during operation. The pullback function is necessary to remove a particular yarn strand from the common passageway after a yarn bit has been severed therefrom for tufting. This is to enable the advancing of another yarn strand of a different color to the tufting station to supply a yarn bit for the next cycle.
In addition to the above Spanel patents, U.S. Pat. No. 3,824,939 and co-pending Spanel Application Ser. Nos. 419,417, 474,465 and 474,266 all disclose various aspects of Spanel tufting techniques.